Faster flaky test case marking

Back-marking a commit’s CI runs as flaky now also filters the ClickHouse query by git_commit_sha, which engages the table’s bloom filter and prunes the scan to only the granules that hold that commit’s runs. On the profiled workload, scans of up to ~888k rows per high-volume test case were pruned down to just the commit’s slice (six to two granules in the sample), so flaky status updates after a CI run complete with less work against the database.